Challenges for the equipment suppliers when selecting equipment are related to the ATEX zone in which most of the equipment is located, the physical and chemical characteristics of the product (light volatility and flammability, potential problems with mechanical seals), and problems with abrasion during the transport of the initial mixture (cereals + water and acid).
All the mentioned problems were noted on the project of relocation and modernization of the factory of ethyl alcohol (produced from corn). The factory had old equipment mainly based on mono pumps at the initial production stage to centrifugal pumps in the distillation sector. The idea of an engineer from the factory was to change the pumps to the same type (purchasing the centrifugal pumps again). Visiting the site Tapflo specialist realized that in most positions no large flows and pressures are required. As a result installation of diaphragm pumps powered by compressed air was offered – a more elegant and technically correct solution. The client trusted Tapflo as a respectable pump manufacturer and agreed to equip production with AODD pumps.
With this change of pump type, the client recorded multiple winnings, and some of the main advantages are:
- Absence of electric current for pump operation in the ATEX zone, therefore less possibility of explosion
- Pump tightness. Unlike centrifugal pumps, diaphragm pumps do not possess rotational parts and therefore sealing the pumps is simpler and lasts longer.
- Possibility of dry run. The factory itself is not at a high technological level and production much depends on the operator. Using diaphragm pumps, the operator has a certain safety time during which the pump can run dry without damage, which is not possible with centrifugal pumps.
- Adjustment of pump capacity is simple, on the site with needle valve, no expensive frequency regulators are needed
- Pump material/Price. Pumps for most applications are made of aluminum, which significantly influenced to the reduction of the purchase price and the investment itself will be returned faster.
- Position substitution. In agreement with the client, a selection of pump sizes has been made in a way that allows pumps to be easily replaced from another position in case of need (sudden breakdown, etc.) and the process continues smoothly
- Easy maintenance
The pumps have been installed and put into operation in 2016, and since then they have been operating 24 hours a day since the factory works in 3 shifts, without stopping. After a month, the problems appeared in a single position that transported hot alcohol from the distillation column. The Tapflo service team opened the pump and found out that there was unexpected wear on the suction and discharge manifold, and there was certain wear visible on the pump’s working chambers/casing. These damages are connected to the alcohol temperature – the influence of hot alcohol on the aluminum from which the pump casing was made. For this position, Tapflo changed the pump to one made of AISI 316 stainless steel, and since then there was no problems with this position.
